This invention relates to a node apparatus for packet communication, which is designed to forward packet data, and more particularly to a technology for complete connection of an extension module.
Conventionally, the node apparatus for packet communication has a processing unit, a network interface, and a switching unit. The processing unit executes a routing program to create a destination table. The network interface receives and forwards packet data with a network line. The switching unit connects the network interface with another interface.
Upon reception of a packet, the network interface retrieves internal routing information of the packet from the destination table. Next, the network interface adds the retrieved internal routing information to the packet, and forwards the packet to the switching unit. The switching unit extracts the internal routing information from the forwarded packet. Then, the switching unit forwards the packet to the network interface according to the extracted internal routing information. In this manner, the node apparatus for packet communication forwards the packet.
Recent popularization of an Internet Protocol (IP) network has heightened a communication speed and further a level of operation. As a result, the node apparatus for packet communication is now required to provide processing functions requested by a user in addition to the basic packet forwarding operation.
JP 2004-158044 A discloses a conventional technology of providing processing functions required by a user. According to this conventional technology, authenticated program modules are stored in a module server.
The software program module provides a processing function required by the user. In response to a request from the user, the module server transmits the software program module to the node apparatus for packet communication. Upon reception of the software program module, the node apparatus for packet communication executes the received software program module.
This conventional technology is characterized by authentication of developers of software programs. Specifically, data of a developer of the software program module is registered in the module server in advance. Then, a digital signature of the developer added to the software program module is compared with the preregistered data of the developer so that the software program module can be authenticated.
The conventional technology is further characterized by authentication of users who use the software program module. Specifically, the users who utilize the software program module are registered in the module server in advance. Then, the module server transmits the software program module only to node apparatuses for packet communication managed by the registered users.